Williams recovered his poise after a mid-match slump to deny his friend and practice partner a title won by the game's greatest names and in the process restored himself to No 1 in the provisional rankings. But it was touch and go as he twice squandered big leads against a player who thrashed him 9-1 in the 1997 event.
Stevens threatened to send the match into a deciding frame but after working his way through the reds in a tight 18th frame, he missed the black after potting the final one. Williams then potted a tricky yellow and mopped up the remaining colours to complete his 10-8 success. The clenched fist salute that followed was as much in relief as delight.
"I was getting ready for 9-9," the new champion said. "In fact, I was beginning to feel I might lose the match. Thoughts of losing to John Higgins in the Grand Prix final, when I had been 6-2 up, kept coming into my mind."
Williams added: "I was feeling a lot of tension at the end and I imagine it was the same for him. I just put all my eggs in one basket to make sure the yellow went in. It's nice to be No 1 on the rankings but it will mean more to me if I'm still there at the end of the season."
It was a second successive near-miss in the UK Championship for Stevens after he lost to Higgins 12 months ago.
"I really expected to get the black but I just took my eye off it," he said. "I missed too many balls in the match that came back to haunt me. But maybe I'll be back next year to make it third time lucky."
Williams followed in the footsteps of Steve Davis, Alex Higgins, Jimmy White, Hendry and John Higgins in winning the prestigious title and the left-hander's victory, before a capacity crowd at the Bournemouth International Centre, ended an 11-year wait for the first Welsh champion since Pontypool's Doug Mountjoy defeated Stephen Hendry in at Preston's Guild Hall in 1988.
UK CHAMPIONSHIP FINAL (Bourne mouth): M Williams (Wal) bt M Stevens (Wa) 10-8. Frame scores (Williams first) 24-67, 0-81, 72-16, 67-4, 71-46, 76- 8, 71-59, 65-32, 0-68, 27-73, 47-63, 19-110 (110 break), 67-63, 56-21, 62-22, 25-80, 0-71, 54-51).Reuse content